The tournament was held behind closed doors last year. This time around, with COVID vaccines widely available, fans were welcomed back. But it wasn't easy to get in, CBS2's Kevin Rincon reported.
The scenes throughout the day were what many hoped to avoid: hundreds packed in tight while trying to get through security.
"We first were in another line, but I had my pocketbook. I didn't realize that would be a longer line, so then my son drove, put it in his car. Now we're back in line... but it's still not that fast," said a fan from Connecticut who waited in line for nearly an hour.
Even the pros had to wait.
"I guess we got all the crowds back and ready to go," said Anru Fourie, a professional tennis player from South Africa.
The lines stretched well past the boardwalk and down the road to Citi Field.
"I guess, I'm in line. I don't know how much longer I can wait," said Pittsburgh-native Anita Davis. "Right now, I'll wait as long as I can."
In some cases, fans missed the early matches because of the wait.
The U.S. Tennis Association said it's looking at ways to get fans through security faster. It said crowds were partially to blame for the delays.
In a statement, the USTA said fans arrived later than usual this year, the NYPD held some fans back on the Citi Field side of the boardwalk to prevent overcrowding, and fans appeared to be bringing an "inordinate number of bags" that had to be screened.
"Previously, the number of patrons arriving to the grounds prior to 11 a.m. averaged approximately 10,000. This year, the number arriving prior to 11 a.m. was only 3,000," the statement said.
The statement added, "The process to check proof of vaccination seems to be working smoothly and is not a major contributor hampering entrance to the site."
Some fans said they didn't mind waiting for vaccination statuses to be checked.
"Love it, I'm all for it, because I believe in the vaccine. I think it's the one way that we're going to get this pandemic under control, and frankly I don't want to be around people who are not vaccinated," said Betsy Bonds from Queens.
CBS2's Kevin Rincon contributed to this report.
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